Item of footwear

ABSTRACT

The invention relates to an item of footwear in which is provided a mid-sole (10) with features that provide comfort to the wearer when walking. An item of footwear comprising: a sole (1) comprising a mid-sole (10), the mid-sole having a first major surface (11) for facing the foot of a wearer, a second major surface (12) opposite the first, the mid-sole (10) having an inner edge (13) corresponding to the inside of a wearer&#39;s foot and an outer edge (14) corresponding to the outside of a wearer&#39;s foot; and a securing means for securing the item of footwear to a foot of a wearer such that the first surface (11) of the sole (1) contacts the foot, wherein: the mid-sole (10) has formed therein a plurality of generally transverse grooves (20) and a generally longitudinal primary groove (30a), thereby dividing the sole (1) into an array of lands (50); and the primary groove (30a) is substantially parallel to the outer edge (14) of the sole (1) over a majority of the length of the sole (1) and defines with 15 the transverse grooves (20) a plurality of lands (50).

The invention relates to an item of footwear in which is provided amid-sole with features that provide comfort to the wearer when walking.

It is known to provide grooves in the soles of footwear to increase theflexibility thereof. Such footwear is generally designed for sportinguse and not for comfort. There is therefore a need to providecomfortable footwear designed for everyday usage.

Accordingly, there is provided an item of footwear as defined by theappended claims.

For a better understanding of the invention and to show how the same maybe put into effect, reference will now be made, by way of example only,to the accompanying drawings in which:

FIG. 1 shows the underside of an item of footwear in accordance with thepresent invention;

FIG. 2 shows a cross-sectional view through the mid-sole of the item offootwear of FIG. 1; and

FIG. 3 shows a schematic close-up cross-section of the item of footwear.

FIG. 1 shows an embodiment of an item of footwear in accordance with theinvention.

The item of footwear comprises a sole 1. The sole 1 comprises a mid-sole10. The mid-sole 10 comprises or is formed from: ethylene vinyl acetate(EVA) and/or expanded foam (such as biodegradable expanded foam).

An optional outsole 40 may be provided. The outsole 40 may comprise orbe formed from: rubber. As can be seen from FIG. 1, the outsole 40 maybe textured (in addition to the grooves described below) to provideadditional grip.

The mid-sole has a first major surface 11 for facing the foot of awearer and a second major surface 12 opposite the first 11 facing awayfrom the foot of the wearer. The mid-sole 10 has an inner edge 13corresponding to the inside of a wearer's foot and an outer edge 14corresponding to the outside of a wearer's foot.

The mid-sole 10 includes a forefoot region A arranged to support theforefoot of a wearer of the item of footwear. The forefoot region Aextends over the forwardmost 15% to 24% of the length of the mid-sole10. The mid-sole 10 includes an arch region B arranged to support thearch of the foot of a wearer of the item of footwear. The mid-sole 10includes a heel region C arranged to support the heel of a wearer of theitem of footwear. The heel region C extends over the rearmost 29% to 39%of the length of the mid-sole 10. The arch region B extends from theforefoot region A to the heel region C.

The item of footwear comprises a securing means (not shown) for securingthe item of footwear to a foot of a wearer (for example, the securingmeans may be a strap such as in an open shoe, or an upper, if the itemof footwear is a closed shoe). When in use the first major surface ofthe sole supports the user's foot. The first major surface of themidsole 10 can contact the user's foot directly or an insole can beinterposed between the midsole 10 and the user's foot. The term midsoleused in the specification should be understood to refer to a componentwhich is: sandwiched between an insole and an outsole, or contacts theuser's foot directly and is provided with an outsole; or is used in ashoe without an insole or outside and provides itself the contactsurface for a user's foot and the ground.

A plurality of generally transverse grooves 20 are formed in themid-sole 10. The transverse direction extends from the inside edge 13 tothe outside edge 14, perpendicular to the longitudinal direction of theitem of footwear. Preferably, the plurality of generally transversegrooves 20 each extend from the inside edge 13 to the outside edge 14.

The plurality of generally transverse grooves 20 are preferablysubstantially arc-shaped. That is, the transverse grooves 20 are curvedsuch that their midpoints are further forward on the midsole 10 thantheir outermost extents.

The radius of curvature of the plurality of generally transverse grooves20 increases with increasing distance from the rearmost point of themid-sole 10. In this way, the transverse grooves 20 near the heel of theitem of footwear have a smaller radius of curvature (they are morecurved) than the transverse grooves 20 near the frontal end of the itemof footwear.

Each of the plurality of generally transverse grooves 20 is spaced fromits nearest neighbour by a distance in the range 8 mm to 14 mm.

The mid-sole 10 comprises a generally longitudinal primary groove 30 a.The generally longitudinal primary groove 30 a extends over at least 50%of the length of the midsole 10 in the longitudinal direction X, andpreferably at least 70%. The longitudinal direction X extends from therearmost point of the heel of the item of footwear to the forwardmostpoint. At least a forward portion of the primary groove 3 a is a arcuatein form when viewed in a plan view, as seen in FIG. 1.

More preferably, the mid-sole 10 comprises a second generallylongitudinal groove 30 b. The second generally longitudinal groove 30 bextends in the longitudinal direction through at least 50% of theforefoot region, the secondary groove being substantially parallel withthe primary groove. The second groove 30 b is arcuate in form whenviewed in a plan view, as seen in FIG. 1. Most preferably, only the twolongitudinal grooves 30 a, 30 b are provided.

The primary and secondary grooves may be spaced apart by a distance inthe range 25 mm to 40 mm.

The depths of the transverse grooves are preferably in the range 7 mm to12 mm.

The depths of the longitudinal grooves are preferably in the range 10 mmto 12 mm.

The thickness of the mid-sole 10 has a general taper such that the heelregion C has a greater depth than the forefoot region A. Optionally, thedepths of the grooves 20, 30 a, 35, 36 may be greater in the heel regionC. For example, the depths of the grooves 20, 30 a, 35, 36 in the heelregion C may be in the range 7 mm to 12 mm, with the grooves 20, 30 a,30 b in the forefoot region A and arch region B having a depth in therange 5 mm to 10 mm.

Together, the longitudinal and transverse grooves 20, 30 a, 30 bdividing the sole into an array of lands 50. As can be seen from FIG. 2,the lands 50 are regions of the mid-sole 10 that are formed integrallywith an uninterrupted substrate layer 70 of the mid-sole 10. Theuninterrupted substrate layer 70 is shown by line Y in FIG. 2. Theuninterrupted substrate layer 70 of the mid-sole 10 has a minimumthickness of 5 mm.

The uninterrupted substrate layer 70 is flexible and so forms a hingeallowing a degree of relative movement between the lands 50. In use ofthe item of footwear, this flexibility allows the mid-sole 10 to deformwith the foot of the user. The inventor has discovered that thecurvature of the grooves 20, 30 a, 30 b can be designed to achieve animprovement in the comfort of the wearer. Specifically, it is preferableif the primary longitudinal groove 30 a is shaped to follow the path ofmaximum contact between a wearer's foot and the ground. A normal stepcommences with impact of the heel with the ground. As the foot rollsfrom the heel to the toes, the point of greatest contact with the groundtravels along the outside of the foot.

It has been found that configuring the primary longitudinal groove 30 ato follow the outer edge 14 of the mid-sole 10 provides improvedcomfort. In this way, the lands 50 forming a row along the outer edge 14have substantially equal width. Preferably, the lands 50 forming a rowalong the outer edge 14 have a width (in the transverse direction) inthe range 20 mm to 30 mm.

The shape of the mid-sole 10 is of a typical shape in plan view, withthe edges 13, 14 being generally parallel in the heel region C.Therefore, the primary groove 30 a extends generally centrally throughat least a portion the heel region C such that the mid-sole 10 isdivided into two longitudinal rows of lands 50, with each row 50 havingsubstantially the same width in the transverse direction.

The secondary groove 30 b begins/terminates at or near the inner edge 13of the mid-sole 10 in the arch region B. Between the secondary groove 30b and the outside edge 14, the mid-sole 10 is divided into twolongitudinal rows of lands 50, with each row 50 having substantially thesame width in the transverse direction. Between the secondary groove 30b and the inside edge 13, the mid-sole 10 includes a single row of lands50 that preferably increase in width in the transverse direction fromthe arch region B towards the portion of the mid-sole 10 correspondingto ball of the wearer's foot.

Whilst it is possible for the primary longitudinal groove 30 a toterminate at the rearmost point of the mid-sole 10, it is preferablethat the primary longitudinal groove 30 a terminates in the heel regionC. In such an embodiment, the heel region C of the mid-sole 10 comprisesa central land 52 located generally centrally in the transversedirection. The central land 52 receives the primary impact during theheel strike. The central land 52 is preferably surrounded around itsentire perimeter by a plurality of surrounding lands 53. The centralland 52 is preferably circular, when viewed in a plan view as in FIG. 1,and the surrounding lands 53 are preferably arc-shaped, being separatedby groove 36 which extend radially outwardly from the land 52, whenviewed in plan view, as in FIG. 1. The central land 52 may have a radiusof approximately 15 mm.

The central land 52 is surrounded by a groove 35, which may meet theprimary groove 30 a, and separates the central land 52 from thearc-shaped lands 53. The radially extending grooves 36 extend outwardlyfrom the groove 35 to separate the neighbouring arc-shaped lands 53.

Since the central land 52 is subject to large forces, an insert (e.g. arigid insert) is provided in the central land. Similarly, inserts 103may be provided in one or more of the arc-shaped lands 53. The inserts102, 103 may be formed of or comprise rubber.

The mid-sole 10 includes a fowardmost region 54 within the forefootregion A. Preferably, the transverse and longitudinal grooves 20, 30 a,30 b do not extend into the forwardmost region 54. This region is wherethe wearer pushes off in the latter part of each step and so it ispreferable to provide an insert 101 is provided in the forwardmostregion 54. The insert 101 may be formed of or comprise rubber.Preferably, the insert 101 is textured to provide grip.

The forwardmost region 54 may, for example, extend over the forwardmost20% of the length of the mid-sole 10 in the longitudinal direction.

As can be seen in FIG. 2, the transverse and longitudinal grooves 20, 30a, 30 b have a generally tapered cross-section (perpendicular to theirlengths) such that the grooves 20, 30 a, 30 b are wider when they meetthe second major surface 12 than at their deepest points. The width ofthe openings of the grooves 20, 30 a, 30 b at the second major surface12 is in the range 1 mm to 3 mm.

As mentioned above, the item of footwear preferably does not comprise anoutsole 40. An outsole 40 could be provided. This would be a layerformed of or comprising rubber. As shown in FIG. 3, the outsole 40 couldcover the mid-sole 10 such that it extends within each groove 20, 30 a,30 b, 35, 36 but does not entirely fill the groove. In other words, theoutsole 40 is wrapped around the lands 50, 52, 53 of the mid-sole 10.

1. An item of footwear comprising: a sole comprising a mid-sole, themid-sole having a first major surface for facing the foot of a wearer, asecond major surface opposite the first, the mid-sole having an inneredge corresponding to the inside of a wearer's foot and an outer edgecorresponding to the outside of a wearer's foot; and a securing meansfor securing the item of footwear to a foot of a wearer such that thefirst surface of the sole contacts the foot, wherein: the mid-sole hasformed therein a plurality of generally transverse grooves and agenerally longitudinal primary groove, thereby dividing the sole into anarray of lands; and the primary groove is substantially parallel to theouter edge of the sole over a majority of the length of the sole anddefines with the transverse grooves a plurality of lands.
 2. The item offootwear of claim 1, wherein in an arch region of the midsole the landshave a substantially equal size in the transverse direction.
 3. The itemof footwear of claim 1 wherein the plurality of generally transversegrooves are arcuate when viewed in plan view with their outer portions,nearer to the inner and outer edges of the mid sole being rearward oftheir central portions.
 4. The item of footwear of claim 3 wherein theradius of curvature of the plurality of generally transverse groovesincreases with increasing distance from the rearmost point of themid-sole.
 5. The item of footwear of claim 1, wherein: the mid-soleincludes a heel region arranged to support the heel of a wearer of theitem of footwear; the heel region comprises a central land, surroundedaround its entire perimeter by a plurality of arc-shaped lands.
 6. Theitem of footwear of claim 1, wherein the heel comprises a generallycircular central land, surrounded by a circular groove, circular in planview and a plurality of radial grooves extending radially outwardly fromthe circular groove, when viewed in plan view, with the arc-shaped landsdefined between the circular groove and the radial grooves.
 7. The itemof footwear of claim 5, wherein the central land has a radius ofapproximately 15 mm.
 8. The item of footwear of claim 6, wherein aninsert is provided in the central land.
 9. The item of footwear of claim4, wherein an insert is provided in one or more of the arc-shaped lands.10. The item of footwear of claim 5, wherein the heel region extendsover the rearmost 29% to 39% of the length of the sole.
 11. The item offootwear of claim 1, wherein the plurality of generally transversegrooves are spaced apart by a distance in the range 8 mm to 14 mm. 12.The item of footwear of claim 1, wherein: the mid-sole includes aforefoot region arranged to support the forefoot of a wearer of the itemof footwear; and the mid-sole further comprises a generally longitudinalsecondary groove in the forefoot region, the secondary groove beingsubstantially parallel with the primary groove.
 13. The item of footwearof claim 12, wherein the forefoot region 4 extends over the forwardmost15% to 24% of the length of the sole.
 14. The item of footwear of claim12, wherein the secondary groove terminates at or near the inner edge ofthe mid-sole.
 15. The item of footwear of claim 12, wherein the primaryand secondary grooves are spaced apart by a distance in the range 25 mmto 40 mm.
 16. The item of footwear of claim 1, wherein: the mid-soleincludes a fowardmost region; and the grooves do not extend into theforwardmost region.
 17. The item of footwear of claim 16, wherein aninsert is provided in the forwardmost region.
 18. The item of footwearof claim 16, wherein the forwardmost region extends over the forwardmost20% of the length of the sole in the longitudinal direction.
 19. Theitem of footwear of claim 1, wherein the depths of the transversegrooves are in the range 7 mm to 12 mm.
 20. The item of footwear ofclaim 1, wherein the depths of the longitudinal grooves are in the range10 mm to 12 mm.
 21. The item of footwear of claim 1, wherein: themid-sole includes a heel region arranged to support the heel of a wearerof the item of footwear; and the depths of the grooves in the heelregion are in the range 7 mm to 12 mm.
 22. The item of footwear of claim1, wherein each grooves has a generally tapered cross-section, whenviewed in a cross-section taken transversely across the groove.
 23. Theitem of footwear of claim 1, wherein the width of the openings of thegrooves at the second major surface is in the range 1 mm to 3 mm. 24.The item of footwear of claim 1, further comprising an outsole, whereinthe outsole extends into each groove.
 25. (canceled)
 26. (canceled) 27.The item of footwear of claim 24, wherein the mid-sole has a minimumthickness of 5 mm.
 28. An item of footwear comprising: a sole comprisinga mid-sole, the mid-sole having a first major surface for facing thefoot of a wearer, a second major surface opposite the first, themid-sole having an inner edge corresponding to the inside of a wearer'sfoot and an outer edge corresponding to the outside of a wearer's foot;and a securing means for securing the item of footwear to a foot of awearer such that the first surface of the sole contacts the foot,wherein: the mid-sole includes a heel region arranged to support theheel of a wearer of the item of footwear; and the heel region includes acentral land, surrounded around its entire perimeter by a plurality ofarc-shaped lands, the lands being defined by a plurality of groovesformed in the mid-sole.
 29. The item of footwear of claim 28, whereinthe heel region extends over the rearmost 29% to 39% of the length ofthe sole.
 30. The item of footwear of claim 28, wherein the heelcomprises a generally circular central land.
 31. The item of footwear ofclaim 30, wherein the central land has a radius of approximately 15 mm.32. The item of footwear of claim 30, wherein an insert is provided inthe central land.
 33. The item of footwear of claim 28, wherein aninsert is provided in one or more of the arc-shaped lands.
 34. The itemof footwear of claim 28, wherein the depths of the grooves are in therange 10 mm to 12 mm.
 35. The item of footwear of claim 28, wherein eachgroove has a generally tapered cross-section, when viewed incross-section taken transversely across the groove.
 36. The item offootwear of claim 28, wherein the width of the openings of the groovesat the second major surface is in the range 1 mm to 3 mm.
 37. The itemof footwear of claim 28, wherein the mid-sole has a minimum thickness of5 mm